The present invention relates to a battery pack system for hand power tools.
More particularly, it relates to a battery pack system for a hand power tool, which is composed of several battery packs of different structural dimensions, wherein each battery packs has on one side of its housing contact elements for electrical connection between the battery pack and the electrical drive of a hand power tool, and arresting elements for fixing the battery pack on the housing of a hand power tool.
U.S. Pat. No. 5,553,675 discloses a hand power tool, which obtains its energy from a battery pack. The battery pack has on one side arresting elements for fixing the battery pack on a foot of the handle of the hand power tool. Moreover, contact elements are provided at the same side of the battery pack for electrical connection between the battery pack and the electric motor in the hand power tool. The components of the battery pack and the geometry of the arresting elements and contact elements are designed for the use of the battery pack for a special hand power tool.
Conventionally a manufacturer of hand power tools operated by the battery packs provide several battery packs of different structural dimensions and nominal currents. Each battery pack with a corresponding structural dimension, nominal current, power and geometry of the arresting and contact elements is associated with a predetermined type of a hand power tool. The utility of such battery pack system is relatively inflexible, since the application of each battery pack is limited to a predetermined type of a hand power tool.